“Dear Donald Trump, we have been watching you for a long time and what we see is deeply disturbing,” someone wearing the group’s signature Guy Fawkes mask says in the video posted to YouTube last week.

The caption asks hackers to target trumpchicago.com on April 1, which is April Fool’s Day, to start the attack.

“To our fellow hacktivists throughout the world, this is a call to you,” the person in the video said. “We need you to shut down his websites, to search and expose what he doesn’t want the public to know, we need you to dismantle his campaign and sabotage his brand. This is not a war; this is a declaration of total war.”

According to the group’s YouTube account, the video was posted by “the most extreme branch of Anonymous.”

It’s not clear if the hacker collective will follow through with the proposed plan, or if it is an April Fool’s joke.

The hacker group has become known for launching a series of cyber attacks on websites for people, religions, governments and organizations it disapproves of. Most recently they targeted ISIS and the KKK, among several others.